Making eGFP fusion proteins

Hello~
To make one fusion protein, if 2 more additional nucleotides are needed to make the reading frame correct, which amino acid is the best choice for this extra codon in order to have the minimum side effect onto the protein structure?

Although it can be impossible to predict the effect on the structure of a particular protein, I prefer to use Glycine in this situation. My rationale is that it doesn't contribute to steric hindrance, it will not promote unwated ionic interactions, and it does not present a hydrophobic group that would promote folding.